public async Task PatchTodoItem_WithValidId_ShouldReturnNoContent()
{
// Arrange
var mockService = new Mock <ITodoItemService>();
var patch = new JsonPatchDocument <TodoItemDTO>();
mockService.Setup(service => service.PatchTodoItemAsync(1, patch))
.ReturnsAsync(new TodoItem());
var controller = new TodoController(mockService.Object);
// Act
var result = await controller.PatchTodoItem(1, patch);
// Assert
var viewResult = Assert.IsType <ActionResult <TodoItem> >(result);
var noContentResult = Assert.IsType <NoContentResult>(viewResult.Result);
Assert.Equal((int)HttpStatusCode.NoContent, noContentResult.StatusCode);
}